Today nearly all programmers use the Advanced Programming Interface (API) to receive informations about given system values.

现在几乎所有的程序员都采用扩展程序接口（API）来获取操作系统信息。

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Jolicloud is a stripped down operating system that, instead of running software, connects to Web services using their application programming interface (API).

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Bug-for-bug compatibility is a problem, but breaking backward compatibility would be a much bigger problem, so even as the lowest layers of the operating system are revised and rewritten, the layers that applictions talk to (the application programming interface, or API) are carefully tested to ensure that no changes are visible to the application.

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